USDA - Rules state that the kennel must:
Be constructed out of rigid plastic wood metal or material of comparable strength with solid roofs. No cardboard kennels.
Have wheels that can be removed or made inoperable [applies to wheeled kennels only]
Have functional handles on the kennel's exterior to prevent tilting and any direct contact with the animals.
Have all hardware attached nuts bolts and a door that closes securely but not locked allowing personnel to open it in case of emergency.
Have labels with the words Live Animal in letters at least 1-inch tall on the crate's top and on at least one side.
Have upright arrow labels indicating kennel's correct position.
Contain some type of bedding either shredded paper or towels to absorb any "accidents".
Contain two dishes, one for food and one for water, attached to the inside of the kennel door. They must be easily accessible to Delta agents without opening the kennel door.
Display feeding instructions and food if applicable. These instructions should be affixed to the top of the kennel along with shipper and consignee information.
Not be made entirely of welded mesh wire mesh wicker cardboard or collapsible materials.